April 14, 2012
HomeCode SnippetsPerl Read File Line by Line

Perl Read File Line by Line

By  Code Snippets  0 Comments

The following Perl code reads and replace some text in a file. Two code snippets are provided to read a small file and a large file:

Reading a Small File

Perl
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
#!/usr/bin/perl
 
# Open file for reading
open(IN,"in.txt") or die "Cannot open file: $!\\n";
 
# Open file for writing
open(OUT, ">out.txt");
 
# Read the entire file into an array
@file = ;
 
# Line by line
foreach $line (@file)
{
# Replace text in line
$line =~ s/txt1/txt2/g;
 
# Print the modified line
print OUT $line;
}
 
# Close files
close IN;
close OUT;

Reading a Large File

Perl
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
#!/usr/bin/perl
 
# Open file reading
open(IN,"in.txt") or die "Cannot open file: $!\\n";
# Open file for writing
open(OUT, ">out.txt");
 
# For each line
while()
{
# Replace text in line
$_ =~ s/txt1/txt2/g;
 
# Write current line
print OUT $_;
}
 
# Close files
close IN;
close OUT;

More from my site

Tags:

About Author

Mohammed Abualrob

Software Engineer @ Cisco

Add a Comment

Your email address will not be published. Required fields are marked *